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do this, for we do not want to provide ordnance any heavier than what will penetrate 6 inches of Appendix No. 4. armour at the range mentioned. The Palliser shell and gas check weigh 260 lbs., and, with a charge of 50 lbs. of powder, the initial velocity is 1,420 feet per second, so that, by calculation, we find the remaining velocity at 3,000 yards to be 1,008 feet per second. Substituting this in the formula we find that the energy is 1,830 foot-tons, which is equivalent to 6472 foot-tons per inch of shot's circumference. Substituting this value again in the formula =), we find that t=7'6 inches, whereas we only require a penetration of 6 inches. But, as before remarked, armour plates have improved in quality since the formula was laid down, and, as the impact at this long range will not be normal, we may say that we have in the 9-inch a gun which will just about effect our purpose, and which an 8-inch would not do.
65. On the chart* I have drawn, in blue, the position of the new works and the limiting line of Penetration zone. penetration; and in Table I, attached, I have shown the various works in their present and proposed
state. I have also shaded, in red, the line of penetration with the existing armament, for the sake of comparison.
66. From the Table it will be seen that, whereas the guns now defending the harbour are sixteen Proposed armament. in number, it is proposed to partially redistribute this armament, so that we can carry out the improved
scheme of defence by the addition only of eleven 9-inch guns, making the total number of twenty-
seven.
67. Taking each work seriatim, I propose, on a flat cliff, about 80 feet high and 1,500 yards from Battery Passir Pan- Mount Siloso, to provide emplacements for two 9-inch muzzle-loading rifled guns of 12 tons and one jang. 64-pounder, to be brought from Mount Palmer Battery. The 64-pounder should be mounted en barbette, between and on a higher level than the 9-inch guns, which should be on "D" racers, the emplacements being designed to secure their wide lateral range to the best possible advantage. The 64-pounder
itself should have an all-round fire, and the battery be designed at the gorge that it may act as a support for the land defences on the left flank of the line. One of the three main roads from the island to the harbour passes immediately in rear of the site selected.
68. Several modifications should be made in the Mount Siloso Battery. The armament should be Mount Siloso Battery. increased by two 9-inch guns and by one 7-inch from Battery Blakang Mati East. Emplacements for Armament. the 9-inch guns, with expense ammunition accommodation, should be constructed on the flat surface towards the point on the upper glacis (see p. 244). The emplacements for the lower 7-inch guns and the 64-pounders may be maintained unaltered, but that for the upper 7-inch should be remodelled, with the view of providing the gun with a land-service carriage, mounted en barbette in a segmental concrete emplacement, so that the gun can fire through an arc of about 270°, the extreme right training being directed on the Cyrene Shoal.
69. The spur in front of the existing horn-work should be occupied by a small ravelin or redan, Occupation of gorge with revetted escarp, the terreplein at its gorge being taken out to the level of the bottom of the ditch spur. of the curtain of the horn-work, entrance into the main battery being effected by a ramp closed with a pair of strong gates. In the salient of this ravelin, in a segmental emplacement, designed also for musketry fire, should be the other 7-inch gun, mounted in a similar manner to the gun just described, and firing through a similar arc of 270 degrees, from the submarine mining field to the 10-fathom patch between Blakang Mati and Fresh Water Island.
70. The concrete escarp wall, as at present constructed, is of minimum section, and, Chinese coolie Improvement of labour at Singapore not being very good at any time, I would propose that a 2 ft. 6 in. facing should be escarp and gorge. given to it of Malacca stone, a cheap, tough conglomerate, which is taken out in handy blocks and becomes hard on exposure to the air. The present gorge parapet should be thrown forward into the hollow in front of the counter-scarp, and its place supplied by a loop-holed wall.
The ditches also should be generally improved. The escarp of the horn-work and its redan should be heightened, and so constructed from re-entering angle to re-entering angle that a chemin des rondes may run all round, from which the hollows and slopes in front may be searched by musketry fire. The present gorge wall should be continued until it meets the cliff on the reverse of the 9-inch gun emplacements, and, in like manner, the loop-holed wall should be carried round the cliff until it meets the flank parapet of the right 9-inch gun.
71. Between the 9-inch battery and the lower 7-inch battery should be constructed a main Magazines. magazine, protected behind the cliff in front, when the present spacious ammunition stores could be strengthened from the inside and converted into expense magazines, with separate supply passages as at present designed.
72. The bastion parapet of the horn-work may be removed, and its place supplied on one side of Stores, &c. the entrance by a small laboratory, and on the other by an artillery store. A cement tank for water may be constructed under the terreplein of the 7-inch battery. I do not recommend that any permanent barrack should be constructed in the work itself, but only a guard-house in the redan. All the buildings in Singapore are very open, and a wooden fabric with attap roof is all that is required here. The interior space in the battery is limited, and any buildings constructed therein would be much hotter and more unhealthy than if erected on the adjacent slopes of Mount Imbeah. In time of war, temporary leantos could be constructed along the line of the gorge wall for the shelter of the garrison on duty.
73. I would therefore propose that the barracks be constructed on Mount Imbeah, and that the Buildings on Mount summit of that hill be occupied by a strong little redoubt with good concrete escarp and defensible by Imbeah. half a company of men.
74. I propose that, in this new work, emplacements should be provided for one 9-inch muzzle- Battery Blakang Mati loading rifled gun of 12 tons and three 7-inch muzzle-loading rifled guns of 7 tons (to be transferred South. from Tanjong Katong Battery) all on 'D" racers, and that the general design of the work should be
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* Not printed.
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